p28 ecu grounding question
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From: joplin, mo, us
p28 ecu grounding question
Just wondering if the following pins are supposed to be able to ohm out to ground..
A23,A26,B1,B2,D21, and D22? I put one lead on the wire and the other to the body ground and each one of these shows ohms. Im needing to know if they are supposed to? This is done with no battery hooked up btw.
A23,A26,B1,B2,D21, and D22? I put one lead on the wire and the other to the body ground and each one of these shows ohms. Im needing to know if they are supposed to? This is done with no battery hooked up btw.
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Re: p28 ecu grounding question
They all perform a ground function and at some time or another they will Ohm out to chassis ground just like you are seeing.
The only thing iffy about your question is that several of those pins run out to sensors meaning that you can't just ground these ECU pins.
They wires need to exist in the harness and run out to the sensors in order to function.
BTW you are missing A24
The only thing iffy about your question is that several of those pins run out to sensors meaning that you can't just ground these ECU pins.
They wires need to exist in the harness and run out to the sensors in order to function.
BTW you are missing A24
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Re: p28 ecu grounding question
Why are you doing these tests?
The info below refers to the pins in the wire harness connectors:
A23, A24, A26, and B2 supply ground for the main relay and/or ECU.
B1 inputs voltage from the main relay to the ECU.
D21 and D22 inputs voltage from sensors to the ECU, which provides ground (as mentioned).
The info below refers to the pins in the wire harness connectors:
A23, A24, A26, and B2 supply ground for the main relay and/or ECU.
B1 inputs voltage from the main relay to the ECU.
D21 and D22 inputs voltage from sensors to the ECU, which provides ground (as mentioned).
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Re: p28 ecu grounding question
P06 ECU
A25 and B1 they are interconnected inside the ECU and you should find 12 positive volts,
and some of these pins A23,A24 and A26 logic ground are interconnected inside the ECU
B2 is a logic ground and isn't interconnected with any other pin inside the ECU,
ECU chassis do not supply ground to the circuit board and is not connected on any way to it,
four ground wires run from the ECU to the junction ground bolt at the thermostat housing and you shouldn't have a lot of resistance between the battery negative and these pins
A25 and B1 they are interconnected inside the ECU and you should find 12 positive volts,
and some of these pins A23,A24 and A26 logic ground are interconnected inside the ECU
B2 is a logic ground and isn't interconnected with any other pin inside the ECU,
ECU chassis do not supply ground to the circuit board and is not connected on any way to it,
four ground wires run from the ECU to the junction ground bolt at the thermostat housing and you shouldn't have a lot of resistance between the battery negative and these pins
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